Well, the N4GN tower project schedule slipped another few weeks. I
decided at the very last second to jump on a chance to join the BQ9P
Pratas DXpedition. The erection party (I still can't say that with a
straight face) is set for 12 Dec. Maybe I'll be on the air by the end of
the 10-meter contest.
The only remaining head scratcher I have is how exactly to attach the guys
to the guy anchors. I used those A.B. Chance 66" screw anchors (Dad and I
bent a 1" solid bar into a pretzel installing those things!). This is the
point where a word is truly worth a millipicture, but I'll try. The basic
problem is that the Rohn equalizer plates are made to be attached to a
5/8" eye on one of their anchor bolts, but the head on these Chance
anchors is HUGE compared to that.
My first thought was to use a 5/8" shackle between the anchor and the eq
plate. No dice. It won't even fit properly on the anchor head. 3/4"
won't work either. 7/8" might just fit the head, but is getting too big
for the eq plate.
So, what to do? Here are some options I've considered. I'm really not
comfortable with any of these. Obviously, the guy anchor attachment is
a critical part of the tower! Pse give me opinions or other suggestions!
What would really be ideal--I think--is a 5/8" shackle-like piece of
hardware that has a much bigger than normal open end (more U-shaped than
omega-shaped). Does such exist?
1.0) Forget the eq plate and attach the guys directly to the anchor head
(short lead of 1/4" EHS to turnbuckle to more EHS to Philystran). The
head does have three thimble-like grooves apparently made for utility pole
guys. What do I lose by skipping the eq plate, assuming I regularly
check/adjust the guy tension on all three guys?
1.1) Same as 1.0, but using oversized thimbles at the guy/anchor
attachment.
2.0) Use a 7/8" shackle, but grind the round end down to roughly 5/8" so
it fits the eq plate.
3.0) Pay someone to do some cutting and welding to attach the eq plates to
the anchor head.
3.1) Pay someone to modify the anchor head to a 5/8" eye.
I know there are several folks out there using these anchors, so surely
someone has come up with a good solution!
73,
Tim Totten, n4gn@iglou.com
http://www.iglou.com/n4gn/
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